Extracting value from large power quality monitoring databases

This paper presents three case studies that demonstrate methods for extracting information from large databases of power quality databases, focusing on rms voltage variations (i.e., voltage dips and swells). The first case study presents a case for why temporal aggregation is necessary for computing voltage sag indices. The second case study presents an example where spatial aggregation of rms variation measurements was necessary as the computation of voltage sag indices at the meter level would be incomplete. The third case demonstrates how measurements can be linked using system event records for correlating measurements related to system faults.